Getting the best out of Falcao?

I am Arsenal, mid-way through the second season. My tactic as a whole is great, I haven't conceded in more than 15 games and I am scoring, but I spent quite a bit to bring Falcao to the Emirates, and with my other tactic, he performed well as part of a 2/sometimes 3 striker formation.

But since changing to a 1-striker formation, he hasn't been performing well. The formation is basically a mix between a 4-2-3-1 and a 4-4-1-1. And it doesn't seem like he is just not doing well with the ball, it is that he very rarely gets the ball (He normally gets the least touches apart from my GK and my 2 CB's!)

So what role should I play Falcao, and what else should I do to get him performing?